WASHINGTON — The federal government is giving banks a road map for doing business with marijuana sellers. It's another step toward enabling a legalized marijuana industry to operate in the United States. The Justice and Treasury departments issued new guidance today. It's intended to increase availability of financial services for legal marijuana businesses. But it still preserves the government's power to enforce criminal laws. The guidance comes after Washington and Colorado became the first states in the nation to approve recreational use of marijuana. A citizens' group is hoping to make Alaska the third state to do so.